This application is directed to wireless communications systems, and more particularly to methods and apparatuses for operation mode adaptation in wireless communications systems.
A wireless network may be deployed over a defined geographical area to provide various types of services (e.g., voice, data, multimedia services, etc.) to users within that geographical area. The wireless communication network may include a number of base stations that can support communication for a number of user equipments (UEs). A UE may communicate with a base station via a downlink and an uplink.
The 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) advanced cellular technology as an evolution of Global System for Mobile communications (GSM) and Universal Mobile Telecommunications System (UMTS). The LTE physical layer (PHY) provides a highly efficient way to convey both data and control information between base stations, such as an evolved Node Bs (eNBs), and mobile entities, such as UEs. In prior applications, a method for facilitating high bandwidth communication for multimedia has been single frequency network (SFN) operation. SFNs utilize radio transmitters, such as, for example, eNBs, to communicate with subscriber UEs.
Carrier aggregation (CA) or channel aggregation is used in LTE-Advanced in order to increase the bandwidth, and thereby increase data rates. Carrier aggregation enables multiple LTE carriers to be used together to provide the high data rates required for LTE Advanced. Each aggregated carrier is referred to as a component carrier (CC). For example, the component carrier can have a bandwidth of 1.4, 3, 5, 10, 15, or 20 MHz. In Frequency Division Duplexing (FDD), the number of aggregated carriers can be different in downlink (DL) and uplink (UL). The individual component carriers can also be of different bandwidths. In Time Division Duplexing (TDD), the number of CCs and the bandwidth of each CC are the same for DL and UL.
Multiple-input and multiple-output (MIMO) can also be used to improve communication performance. MIMO multiple antennas can be located at both the transmitter (Tx) and receiver (Rx) end. MIMO may spread a total transmit power over multiple antennas to achieve a power gain that improves spectral efficiency (data rate per bandwidth used). MIMO may also increase signal-to-interference ratio which improves communication reliability.